## Urgent: Spring Compression Problem

1. The problem statement, all variables and given/known data
Use work and energy to solve the following. A .1 kg ball is placed against a massless spring that has a stretch constant 50,000 N/m and is compressed 2 m. The spring fires the ball straight up. a) How far did the ball rise assuming no friction? b) The ball's actual rise was 2m short of the answer in part A. What was the frictional work done by air?

2. Relevant equations
1/2ky^2=mg(h+y)

3. The attempt at a solution
I figured out part A to be 102,038 m... which seems outrageous, but the numbers in this problem are also outrageous. I'm really just struggling on how to do B or even attempt it.
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 I used the equation (KE + PEg + PEs)i = (KE + PEg + PEs)f KEi=0 KEf=0 PEgi=0 PEsf=0 PEsi=1/2ky^2 (y=compression) PEgf=mg(h+y) (h=distance traveled) therefore, 1/2ky^2=mg(h+y) so 1/2(50,000N/m)(4m)^2=.1kg(9.8m/s^2)(h+2m) 100,000Nm=.98N(h+2m) 102,040m=h+2m 102,038m=h

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